The present invention relates to a fixed vane assembly of a turbine engine, said vane assembly comprising a ring of abradable material, and a turbine engine comprising at least one such vane assembly.
An airplane turbojet engine traditionally comprises a high-pressure compressor, a low-pressure compressor, a combustion chamber, a high-pressure turbine engine and a low-pressure turbine engine.
The compressor is intended to increase the pressure of the atmospheric air, the combustion chamber mixes the air that is compressed by the compressor with fuel and burns that mixture, the turbine, placed in the ejected flow, is then driven by that high-temperature gas flow. The turbine serves in particular to drive the compressors.
The compressors comprise rotor vanes and stationary guide vanes to guide the flow between the compression stages.
At the output of the combustion chamber, a stationary high-pressure guide vane assembly is provided, intended to rectify the hot gas flow leaving the combustion chamber before it comes into contact with the high-pressure turbine. This high-pressure guide vane assembly comprises a ring fixed on a casing, called the inner casing, and blades extending radially outwardly. The inner casing ensures the connection between the compressor and the turbine.
The guide vane assembly is made up of several sectors, each fixed on the inner casing.
Each sector comprises, traditionally, a platform from which blades extend radially outwardly and a fastening tab for fastening to the casing extends radially inwardly. The tab comprises two bores intended to be aligned with two bores of the inner casing provided on the side of the high pressure turbine, pins are inserted into these aligned bores, a flange is added downstream of the pins to retain them axially.
This type of turbojet engine is for example known from document FR 2 907 499.
This type of fixing is satisfactory. However, in the aeronautic field, there is a constant search to reduce the mass of the various components.
Moreover, the output of aeronautic engines depends in large part on the control of the gas flow between the fixed parts, such as the guide vane assembly, and the rotor parts, such as the high-pressure turbine. In order to have minimal play, a disc made from an abradable material is fixed on the stator. This ring is designed to ensure sealing with the turbine and to degrade and protect the blades of the turbine in case of accidental contact with the stator. The abradable materials for example have a honeycomb structure.
In document FR 2 907 499, the abradable material is supported by an abradable material support ring fixed on the case using a screw.
It is consequently one aim of the present invention to propose a fixed vane assembly for a turbine engine making it possible to reduce the total length of the turbine engine.
It is also an aim of the present invention to propose a stationary vane assembly of a turbine engine whereof the mass is reduced.